1. Field of the Invention
The present invention relates to a method of correcting the dimension of workpieces such as the brackets for mounting automobile engines, the upper arms or the like automobile parts, the parts of office automation equipments or industrial machinery.
2. Prior Art
Generally, those workpieces have been produced each by slicing metal extrusions in the direction perpendicular to extrusion and into any desired thickness, or by bending the metal extrusions into any desired curvature.
A noticeable variation has been found in the dimension of such sliced workpieces or bent workpieces. The slicing is indeed advantageous in that the workpieces of any sophisticated configuration in cross section can be produced by a simple process. However, the openings present in the sliced workpieces are likely to vary in their dimension in the order of millimeters, thus failing to qualify as precision parts. Further, the workpieces of the other type extruded and subsequently bent do suffer a considerable variation in the extent of `spring-back`, also failing to meet severe requirement of preciseness in dimension.
Thus, the dimension of workpieces produced in such a manner have had to be corrected by machining or likewise treating them, incurring much labor and spending a long time for intricate works.